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Collapsed Lash Adjuster?

BigBrian27

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Hello all,

So I started my 2021 Mustang GT (72K mi) yesterday for the first time since October. When it started it made a tapping noise like a bad lash adjuster but it went away after a few minutes when the oil warmed up.

I started it when I got home tonight and it fired right up without any noise.

Would you be worried, or is this "normal" for something that was sitting 4ish months?

I have a Whipple stage 2 supercharger ready to install but now I'm nervous. I don't want to make matters worse if I install that.
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Hello all,

So I started my 2021 Mustang GT (72K mi) yesterday for the first time since October. When it started it made a tapping noise like a bad lash adjuster but it went away after a few minutes when the oil warmed up.

I started it when I got home tonight and it fired right up without any noise.

Would you be worried, or is this "normal" for something that was sitting 4ish months?

I have a Whipple stage 2 supercharger ready to install but now I'm nervous. I don't want to make matters worse if I install that.
Hello; let me first say i have not done any work on a coyote engine so my reply is more from pushrod engines. The hydraulic lifters became popular long ago basically because no regular adjustment was needed. Solid lifters can give a bit more power but can be noisy.
my second car was a 1957 Pontiac Bonneville. Got it cheaper because one of the lifters would not pump up. Was a simple enough fix back in the day.
That your lifter did pump up is a good sign. Likely just drained off overtime.
 
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BigBrian27

BigBrian27

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Hello; let me first say i have not done any work on a coyote engine so my reply is more from pushrod engines. The hydraulic lifters became popular long ago basically because no regular adjustment was needed. Solid lifters can give a bit more power but can be noisy.
my second car was a 1957 Pontiac Bonneville. Got it cheaper because one of the lifters would not pump up. Was a simple enough fix back in the day.
That your lifter did pump up is a good sign. Likely just drained off overtime.
I've also never had a Coyote apart. I'm assuming it just bled down over the 4 months although that doesn't fill me with confidence.
 

SheepDog

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Could have been a timing chain slapping the slack side on a guide, until the tensioner got oil pressure again. The OEM tensioners are oil pressure only units.

Or a lifter. These also rely on oil pressure
 

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.... I started up my '21 after five months sitting and it made no unusual noises. As if I put it away the night before. Something not right, sorry friend.
 

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BigBrian27

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.... I started up my '21 after five months sitting and it made no unusual noises. As if I put it away the night before. Something not right, sorry friend.
Ahh man, not what I was hoping to hear...

Could have been a timing chain slapping the slack side on a guide, until the tensioner got oil pressure again. The OEM tensioners are oil pressure only units.

Or a lifter. These also rely on oil pressure
I believe it's one of the lash adjusters (lifter) as the sound was most prominent on the passenger side, under the valve cover in about the middle.
 

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Ahh man, not what I was hoping to hear...



I believe it's one of the lash adjusters (lifter) as the sound was most prominent on the passenger side, under the valve cover in about the middle.
You said the noise went away "after a few minutes", but was it really a few minutes, or like 20-30 seconds?
 

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Oil pressure bleed down , after sitting 5 months, and now you most likely will be fine.

Wipple on a 72 k milage engine, that's a bunch of pressure on a moderate to high mileage bottom end . I'll stand corrected if a Coyote is different than the days past , but I don't think so.

Screenshot_20260323-163216~2.webp
 
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BigBrian27

BigBrian27

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Oil pressure bleed down , after sitting 5 months, and now you most likely will be fine.

Wipple on a 72 k milage engine, that's a bunch of pressure on a moderate to high mileage bottom end . I'll stand corrected if a Coyote is different than the days past , but I don't think so.

View attachment 916077
Is 72k really considered "high mileage"?

I come from the world of LS engines where people boost 250k mi engines without a second thought.
 

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Brian , I've never been a fan of boost , especially when the pistons compression and rings haven't been taken into consideration , and a bottom end hasn't been setup for boost . Longevity plays a big factor at least for me .
Those 250k LS motors most likely didn't have longevity boosted before they showed there age.

I'll let a knowledgeable Coyote person answer you question on 72k moderate to high mileage for boost and lasting .
 

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In my opinion 72k is a young motor if it’s just been street driven and taken care of.
Also I wouldn’t sweat the lifter noise unless it comes back.
 
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BigBrian27

BigBrian27

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In my opinion 72k is a young motor if it’s just been street driven and taken care of.
Also I wouldn’t sweat the lifter noise unless it comes back.
It's never been raced or pushed. Just a weekend cruiser now that I have a company truck.
 

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Just broken in.
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